A major 'minor coronary anomaly'

The anomalous origin of the left main coronary artery from the right sinus of Valsalva and coursing between the aorta and pulmonary trunk to reach the left side of the heart was once considered a minor anomaly. This is now recognised to be a cause of sudden cardiac death and myocardial ischaemia that can be fatal. If symptoms of myocardial ischaemia arise from this anomaly patients usually present before the age of 20 years but often there are no prodromal signs or symptoms and sudden cardiac death is the first presentation of this anatomical variant [ 1,2]. Janata et al. [3] in this issue highlight that the diagnosis is all too often made following failed resuscitation secondary to massive myocardial infarction While fatal cardiac arrest occurs in some young patients with this anomaly, other patients have a normal life span. The anomaly can be classified into four major groups according to the course taken by the left main stem in relation to the aorta and pulmonary trunk on route to the left side of the heart. The left main stem can course either (i) anterior to the pulmonary trunk, (ii) posterior to the aorta, (iii) within the ventricular septum beneath the right ventricular infundibulum or (iv) between the aorta and the pulmonary trunk as in the case described in this issue. In the first group there have been no reports of sudden cardiac death or myocardial